6/19/2009

In this photo provided by NASA, an Atlas V rocket blasts off the launch pad headed to the moon, carrying a pair of science probes that will scout out potential landing spots for astronauts, Thursday afternoon, June 18, 2009 in Cape Canaveral, Fla.

WASHINGTON, June 18 -- NASA's two new lunar probes, Lunar Reconnaissance Orbiter (LRO) and Lunar CRater Observation and Sensing Satellite (LCROSS), lifted off Thursday on a landmark mission to scout water sources and landing sites in anticipation of leading astronauts back to the moon in 2020.

The two probes, a powerful lunar orbiter and a smaller spacecraft that will hunt for water ice by crashing into the moon, were launched on an Atlas V rocket at about 5:32 p.m. EDT (2132 GMT) from the Cape Canaveral Air Force Station in Florida.

According to NASA TV, LRO and LCROSS separated about 45 minutes after launch.

"All's well so far. We just accomplished LRO separation, which was obviously a great milestone," said NASA launch director Chuck Dovale.

LRO is a robotic mission aimed at creating a comprehensive atlas of the moon's features, finding possible landing sites, identifying available resources, characterizing the radiation environment by using a special plastic designed to mimic human tissue, and testing new technology.

It is expected to reach the moon on Tuesday morning at 5:43 a.m.EDT (0943 GMT), then will spend a year studying the moon to aid future astronaut missions before NASA turns it over to a science team for a potential years-long extension.

"The robotic mission will give us information we need to make informed decisions about any future human presence on the moon," NASA official Todd May told reporters earlier this week.

LCROSS will search for water ice on the moon by sending Atlas V's spent upper-stage Centaur rocket to impact part of a polar crater in permanent shadows. It will fly into the plume of dust left by the impact and measure the properties before also colliding with the lunar surface.

LCROSS is following in the footsteps of many spacecraft that have intentionally hit the moon. Earlier this month, Japan's Kaguya lunar probe ended its year-long mission with a moon crash. China's Chang'e-1 probe did the same earlier this year.

LRO, the Hubble Space Telescope and other assets in space and sky watchers on Earth are expected to observe the lunar smack down, which is slated to occur in early October. The final collision date depends on when the mission launches. The target crater will be decided about a month before impact.

Past missions have found ample traces of hydrogen suggesting water ice may lurk in the moon's shadowed craters, but NASA hopes LRO and LCROSS will be able to find direct evidence of the wet resource.

There are no guarantees the water ice is actually there, or what kind of shape it is in, mission managers said. Some observations predict ice rinks of the stuff, while others suggest the ice is in blocky chunks or buried, if it is there at all, they added.

"That illustrates the importance of our mission," said Daniel Andrews, NASA's project manager for the LCROSS probe. "Let's go see what it is."

It costs 50,000 dollars a pound to send anything to the moon, so finding water ice or permanent regions of sunlight for solar power stations could be vital to help support future moon bases, NASA officials said.

Thursday's launch of the dual probes occurred one month shy of the 40th anniversary of the first lunar footprints.

The 583-million-dollar mission has been delayed since October 2008 and was slated to launch on Wednesday. But NASA opted to delay the flight by one more day to allow the space shuttle Endeavour to try and launch after a hydrogen gas leak thwarted its initial attempt. The leak reappeared and the shuttle remains on Earth at the nearby Kennedy Space Center in Cape Canaveral, Florida.(Xinhua)